Effects of large-dose of Ambroxol hydrochloride on Toll-like receptor 4/Nuclear transcription factor- kappa B expression in rats with lung injury

Abstract

Objective To investigate the effect of large-dose of Ambroxol hydrochloride on Toll-like receptor 4(TLR4)/ Nuclear transcription factor- kappa B(NF-κB)expression in rat after lung ischemia-reperfusion injury(LIRI), and possible mechanisms. Methods 60 healthy SD rats were randomly assigned into four groups(n=15, each): the first group(control group), the second group(Ambroxol hydrochloride group), the third group(ischemia-reperfusion group, I/R), and the fourth group(I/R + ambroxol hydrochloride group). The second and fourth groups were injected with Ambroxol hydrochloride 0.75g/l by intravenous injection. The first and third groups received equal volume of saline.The LIR-induced pathological changes were observed and graded. The wet-to-dry weight ratio, interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), nuclear transcription factor- κB(NF-κB)were determined. The protein expression of TLR4 in lung tissues was detected by Western blotting. Results Compared with the control group, the I/R group showed that the thickened alveolar wall, alveolar hemorrhage and other inflammatory changes in lung tissues were found, and that the wet-to-dry weight ratio, and expressions of IL-1β, TNF-α, NF-κB and TLR4 were significantly increased.The alveolar hemorrhage, edema and other inflammatory changes in lung tissues were alleviated, and the wet-to-dry weight ratio, the expressions of inflammatory cytokines, NF-κB and TLR4 in lung tissues were significantly decreased in I/R + ambroxol hydrochloride group versus the I/R group,. Conclusions The large-dose of Ambroxol hydrochloride has a protective effect on lung ischemia-reperfusion injury in rat through down-regulating TLR4/NF-κB signaling pathway. Key words: Ambroxol; Acute lung injury; Toll-like receptor 4; Nuclear factor- kappa B